Blender (2.91) crashes immediately when I press render because of animation nodes addon
This is probably because the add-on is not compatible with blender 2.91. You will have to use a version that is compatible with the version, like 2.83. That is most probably the reason why it isn't rendering. It could also be that the animation nodes are so heavy that they ate up all the Ram at that instance. Try to look for an alternative. Do try the first solution, if it still doesn't work, then try for an alternative add-on.